The present invention relates to an appliance for correcting rachidial deformities and essentially scoliosis, which is the major cause of such deformities.
The appliance is intended to be surgically implanted along the deformed part of the rachis or vertebral column of a growing child and to remain there a number of months or years during which it exerts a corrective mechanical action on the profile of the rachis for reducing the initial deformity. When growth is at an end or when the correction obtained is satisfactory, surgery takes place again in order to remove the appliance.
Scoliosis is a disease which deforms the rachis and reaches one or more rarely two segments thereof during the growth period. This deformity is particularly serious because, due to the fact that it combines a horizontal torsion and a flexion in a frontal plane, it develops in the three dimensions in space. It is also an evolutive disease, which starts during the growth phase, probably due to the rotation of one or two vertebral bodies. Scoliosis is in particular an evolutive dynamic disease and several known tests (particularly the bending test) show its at least partially correctable nature at the start of the disease. The deformity subsequently has a tendency to become fixed as a result of the stiffening of the articular parts and deformities of the osseous parts. It is therefore important to correct this deformity as early as possible after its detection.
The presently known treatments for scoliosis are firstly orthopedic and dynamic (wearing a rigid corset, traction exerted on the vertebral column particularly by suspending the patient by the head and kinesitherapy). Surgery is carried out if this treatment is inadequate and the deformity is aggravated. The object of the surgery is, after reducing to the maximum possible extent the deformities, to fix the lesions by means of rigid equipment and arthrodesis to prevent aggravation of the deformity. These methods are sometimes necessary to avoid the worst, but nevertheless have the serious disadvantage of being definitive and of stopping the deformity by stopping growth.